Where is it safe to cruise in 2021?

More than a year after Covid-19 brought cruise ships to a halt, there are clear signs that cruising could be making a comeback.

The U.S. Centers for Disease Control and Prevention (CDC) announced this month that cruises could resume mid-summer – with restrictions – in a move acclaimed by operators and cruise enthusiasts.

That follows months of mounting pressure from the industry, which claims it has been treated unfairly due to coronavirus restrictions, prompting Carnival to consider relocating ships and Florida Governor Ron DeSantis to press charges.

Still, seafarers have a lot to navigate as government regulation and vaccination rollout differ around the world. CNBC’s Global Traveler has looked at what to expect from cruises in 2021.

At this point, U.S. port departures remain a no-go under CDC guidelines, despite calls to restart on July 1. That includes major cruise excursions to Alaska, where Governor Mike Dunleavy is threatening legal action.

However, the Caribbean is full steam ahead – as long as passengers depart from the islands.

Starting in June, Royal Caribbean will run a series of itineraries across the region, starting in the Bahamas and St Maarten. Crystal Cruises will begin departing from the Bahamas in June, while Norwegian will begin departing from Jamaica and the Dominican Republic in August.

Europe is also sailing on.

Greece is the destination of choice for many airlines, with Norwegian and luxury liners Celebrity Cruises, Seaborn and Ponant all planning itineraries with port calls around the Greek islands this summer. MSC Cruises will also operate a series of itineraries across Europe from May, with visits to locations in Italy, Malta, France, Spain, Greece, Croatia and Montenegro.

Venice is included in MSC Cruises’ itineraries, although embarkation from the city’s historic port will soon be a thing of the past as Italian officials have indicated that cruise ships will be diverted to the nearby industrial port under new environmental regulations.

However, some operators, including MSC Cruises, only serve passengers residing in the Schengen zone of the European Union. International visitors should be aware of any residency restrictions and flying to the country of embarkation prior to booking.

Meanwhile, the so-called “cruises to nowhere” remain in full swing. As return flights with no ports of call and mandatory pre-departure tests, they are seen as a low-risk option for vacationers looking to escape.

The no-destination vacations in Singapore have proved so popular that city-state cruise ships accounted for a third of the total number of travelers in the industry last month, pushing operators Royal Caribbean and Genting to extend their seasons into October.

In the UK, companies are also starting with the idea. Starting in June, P&O, Princess Cruises, Disney, MSC Cruises, Virgin Voyages and Royal Caribbean will all sail around the British Isles – many with inland ports.

For the most part, cruises are only available to those who have been vaccinated.

In January, British operator Saga Cruises faced consternation when it became the first cruise line to introduce mandatory vaccination. But now companies are recognizing it as the norm, said Tom McAlpin, CEO and president of Virgin Voyages, Richard Branson’s adult cruise line.

“We know this is the future,” said McAlpin. “As an adult cruise line, we can provide a tightly controlled, safe environment for everyone on board.”

Crystal Cruises, Norwegian, P&O, Viking and Celebrity Cruises have all followed suit by introducing vaccination requirements for adult passengers. Royal Caribbean has mandated vaccines for some routes, including the Caribbean, while Carnival Cruises has yet to announce such measures.

The emphasis on health and safety will also extend to the experience on board. Buffets will be gone and entertainment may be limited as cleanliness is key.

“While traditionally cleaning a ship would have been done in the background … ‘home theater’ will be of greater consumer importance and hospitality brands will put their cleaning protocols at the center,” said Elle Kross, director of strategy at digital marketing firm Movable Ink.

Meanwhile, passengers can expect new technologies, from virtual queues and contactless payments to thermal temperature controls and UV cleaning, to reduce face-to-face contact on board.

“Operators have done a lot of work … leveraging modern technology, implementing new processes, and training employees to work with new policies and guidelines,” said Vijay Achanti, North America hospitality director at the global consulting firm. Capgemini.

With new measures and the announcement of more routes, vacationers seem to be gaining confidence. Bookings for 2021 are on the rise, with Crystal Cruises booking the largest one-day bookings in its 30-year history last month.

The route ahead looks even clearer. Sales of advanced cruise tickets in the US for 2022 so far exceed 2019 for the 2020 season, according to data from Google analyzed by the travel site Trips to Discover, as travelers plan new and rescheduled trips.

Most of those bookings still come from regular cruisers, said Movable Ink’s Kross. Carnival reported last month that 55% of bookings for 2021 to date have come from “brand loyalists.” But newcomers, too, are starting to see cruises as a slice of “pre-Covid normalcy,” she said.

Still, many do this with caution, said Jeanie Johnson of Minnesota tour operator Jeanie’s Journey, who noted that most vacationers opt for suites and log cabins with balconies.

“Even though these cruisers are fully vaccinated and ready to go, they are just a little bit wary,” she continued. “They want access to the outside … just in case.”